WLLH Lawrence update
Fri Apr 4 21:20:36 EDT 2008
Located the major problem with the rooftop antenna, the minor damage I
found is likely to have been caused by an HVAC service tech tripping over
the copper pipe transmission line. It runs behind one of the units suspended
The line was shoted to aluminum flashing that seals a few no longer used
access holes that penetrate the roof.
I now can load enogh power to the antenna where the bridge is now usable.
Look for WLLH Lawrence to reappear Sunday afternoon though possibly at a
reduced level of power.
For the past 6 years this rooftop system has suffered from a 9 ohm
seasonal impedance shift that continues to defy any attempt to track it
It has been one of those things you learn to live with, when it decides to
shift I just move a coil tap back and forth between 2 spots.
The problem has come down to either the 1936 Linco pole has badly corroded
internally or a smiliar type of problem with the top loading hardware.
Kurt Jackson has tried everything possible includind physically smacking
every inch with a wooden baseball bat to replicate the shift with zero
( the shift takes place on the antenna and is not the ATU)
Thats all for now,
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